Author: Peter D. Gray Date: To: exim-users Subject: Re: [exim] default value seems a big low
On Fri, Aug 18, 2006 at 09:26:31AM +0100, Philip Hazel wrote: > On Fri, 18 Aug 2006, Peter D. Gray wrote:
>
> > I think you should at least consider making the limit 0 by default.
>
> I don't like incompatible changes. The limit was introduced for a reason
> (somebody got bitten). I would need a lot of convincing by a lot of
> people before I'd feel that it could be changed.
>
That's ok. As I said, I think you should "consider it". If you have
reasons for leaving it the way it is then that's fine as well.
On the issue of compatibility though, you are between a rock
and a hard place. Compatability is good, but things working
right is better (IMHO). Consistancy is also good.
You have to juggle these competing demands.
> > It seems to me that most (in fact nearly all) of the "rate limiting"
> > settings in exim are turned off (eg queue_only_load).
>
> What about these (they are just a few that I found with a quick grep):
>
> |smtp_accept_max|Use: main|Type: integer|Default: 20|
> |smtp_connect_backlog|Use: main|Type: integer|Default: 20|
> |smtp_max_synprot_errors|Use: main|Type: integer|Default: 3|
> |smtp_max_unknown_commands|Use: main|Type: integer|Default: 3|
>
> You are right, though, that there is inconsistency. It's hard to be
> consistent. In the case of queue_only_load, I think it might be hard to
> pick a number that would be suitable for the huge variety of hardware
> configurations that Exim runs on. Maybe. I'm no expert in exactly what
> the load value means.
>
You are correct. It is becoming increasing hard to work out what the
load average is telling you, even though the definition is very clear.
I have found recently that machines seem to have higher load averages
that I would have predicted from their job mix and they seem to work
well with high loads (solaris/sparc).
